The story takes place in the Kanagawa Prefecture, and centers on 20-year old Keitaro Urashima, a young man desperately trying to be accepted into the prestigious Tokyo University in order to fulfill a childhood promise he made with a girl he now regards as the girl of his life. His obsessive pursuit of this dream is one of the few shining spots of optimism in his otherwise unlucky life. He becomes manager of the Hinata House (日向荘, Hinata Sō?, also known as Hinata Apartments), property of his family and now an all-girls' dormitory.

After much tribulation, he wins their respect and eventual affection. From the beginning of the series, he suffers physical damage and abuse, which continues and increases as the series goes on. (In the anime the girls are openly shown being less hostile towards Keitaro, many fans have seen this as a weakness, saying that because of this the emotional scenes – particularly those between Keitaro and Naru – don't stand out as much as they do in the manga.)